Dielectric separator.



No. 888,432. PATENTED MAY 19, 1908. H. M. SUTTON '& W. L. & E. G. STEELE. DIELECTRIC SEPARATOR.

APPLICATION FILED SEPT. 3, 1907.

UNITED sTATEsrgnTENT OFFICE.

HENRY M. SUTTON. WALTER L. STEELE. AND EDWIG. STEELE, OF IQALLAS. TEXAS.

Specification of Letters Patent.

Patented May 19, 1908.

Original application-filed September 24. 1904.l Serial 225.852. Divided and. this application filed September 3, 1907. S'erial No. 391.132.

T o all whom. it ma y concern:

Be it known that we, HENRY M. SUTTON, WALTER L.` STEELE, and EDWIN G. STEELE, citizens of the United States, residing at Dallas, in the county of Dallas and State of Texas,

have invented certain new and useful Improvements in Dielectric Separators, of which the following is a specification, reference being had therein'to the accompanying dra-wing.

This invention relates to an apparatus for separating substances of different dielectric.

capacities and comprises a division of our application filed September 24, 1904, Serial No. 225,852 embodying the form thereof where a continuous convective charge or current is used.

The inyfention hasfor an object to provide means for conveying the material to be separated into component particles int-o the field of means for producing in the material dielectric hysteretic impedance or a lag of charge in connection with means for collecting the separated particles of material according to the difference in time that said particles maintain theirpolarity due to the .impedance generated therein. This effect -may be produced byany desired means as, for instance, feeding the material to an extrem'ely unbalanced electro static. field. Such a condition is established whenever a series of metallic points `or a sharp edge is connectedl to a source ofstatic or high tension electricity so as to produce a convective current and the latter is allowed to escape across the intervening space to a surface of conducting material which is. grounded to the earth or connected to the opposite pole of the electric source of energy to that con- 40`nected to the y points or sharp edge.

produces a vey highly concentrated electro `static field, and when .the commingled mass of particles is fed into such a field the particles are unable to seek a perfectI equilibrium as the conducting surface over which they are fed has absolutely no power of repulsion, and .the points or sharp edge have absolutely no power of attraction. The fact that the l articles adhere to such a conduct-ing surface .1s due to the -residual charge imparted to these particles by the' passage .of electricity fromthe points-or sharp edge to the grounded surface and only occurs in aline approximately opposite the points. If a sharp point This be attached to the charged surface of a static machine and a plate of conducting material grounded to the earth be placed a short distance from such oint there will be a constant convective ow of electricity` from the point to the plate in contradistinction to a disruptive discharge produced by a round surface. Itis impossible under these conditions to charge the point with its full potential as it is discharged as fast as the current is being delivered to it from the machine. In fact, the point is receding from the full potential instead of approaching it, and by this means an unbalanced electro static field is established. Now if a particle o'f any substance be movably suspended between the plate and point of the conductor it will be attracted to the plate and adhere indefinitely to it so long as this convective charge is maintained as there will be no equilibrium established in which the substance charged can reach a potential that will enable it to be attracted to the point or be repelled from the grounded surface even if such surface be con-V nected to the opposite pole of the static machine from that of the point. It will thus be seen that dielectric hysteretic impedance is generated in any substance to a more or less extent when that substance is subjected to an unequal electro static 'stress or strain. This impedance or lag of charge may be produced by various characters of current, for instance, an alternating, pulsating or varied static charge as set forth in our Patent. $813,063, dated February 20th 1906, 'or by the means herein disclosed where a continuous convective current of one polarity is used and the material brought adjacent to the charging point and there charged with electricity of the same sign as that escaping from the point thus establishing in the material opposite' electrical conditions upon its surfaces if the grounded conducting surface be dis osed adjacent to the materia ther and further objects and advantages of the invention will be hereinafter set forth and the novel features thereof defined by the ap ended claims.

n the drawings z-Figure 1 isa perspective with parts in section illustrating the electrical connections, and Fig. 2 is a vertical 'cross section of the separator.

` Like numerals refer to like parts in the several gures of the drawing.

The letter A designates a hopper which is mountedin any desired manner, for instance, upon a frame constructed in accordance with the requirements of the machine. The material to be separated is f'ed from the lower portion of the hopper by means of the spout A3 into the shaker pan A4 which `is pivotally supported by hangers A5 and connected to the eccentric D" upon the shaft D by means of the strip D2. This by its reciprocatory motion feeds the material upon the spreader tray F. This tray is preferably formed of metal and has its bottom fluted or ribbed, as shown at F in Fig. 1, the delivery edge there'- of being left perfectly smooth as indicated at F3. This tray is given a side shake by means of the eccentric F3 mounted on the shaft F4 and connected to the tray Vby means of the s strip F5 said tray being mounted to reciprocate on the rods F by means of the bearings F7 upon the bottom of the tray. The tray` is also given a downward inclination toward the conducting surface, which in the present instance is shown as a metallicroller G. This roller G may be constructed of metal or good conducting mat-erial, and bothl it and the spreader tray F are electrically Iconnected'to the ground by means of the line C (Fig. 1)

so that they are incapable of sustaining ay charge of electricity which may be imparted to them, as such charge would be immediately grounded. This connection may be any desired means, forinstance, the wire C from the tray .to the wiper C2 bearing on the shaft G of the roller. v

Adjacent to the roller G are one or more thin metallic rods H each provided with a series of metallic points H directed toward the surface of the roller by which a flow .of current is maintained through the rods. A'ny other desired means may be used for produc,- ing such a current at thercharging point. The charging means is connected to one pole of the electro static generator C3 orto any other source that isv capable of supplying static electricity, and the current is conducted therefrom to the charging means by line C10 through which a constant charge of one polarity is conducted.

The material to be treated is fed from the tray upon the roller'electrode, as just described and in passing the pointsor charging means from which the convective current of electricity is constantly passing to the roller a dielectric hysteretic impedance or lag of charge is set up 1n certain particles of the mass, while others remain unaffected. These unaffected particles drop upon` the division plate I by centrifugal force due to the motion of the roller as it revolves in the direction of said platefrom which they are discharged into the chute I and conducted to a recepta cle." The particles which have small dielectric impedanceare drawn closer to the face of the roller and thus pass above the division plate and drop into chute I2, while those which have the greatest impedance would remain adhered to the roller and are thus carried past-the adjustable plate T4 so that they may be discharged into the chute I3, and this disposition of the material adhering to the roller may be accomplished by releasing means, preferably, an electrically charged rod or terminahH2 disposed at the back vof the roller and connected by the line C4 with a source of static electricity whose polarity is opposite to that supplied to'the charging means, for instance, to the o posite side of the generator C3, as shown in ig. 1.

To eHect a continuous orconstant charge on the rod H2 and regulate the charge, a regulator Cis shown inserted in line C?. provided with the pointed discharge terminal O ad? justable in its base O2 relative to a rounded terminal O3 opposite thereto. This regulator determines the amount of charge supplied to the particles as the amount of current flowing therethrough proportionately determines the degree of supply at the points because circuit is established from the points through the separating electrode and releasing rod tothe regulator. The necessary amount of current may be thus `governed `relative to the material to be separated. ln l order that the division plate I disposed adj acent to the roller shall not retain the charge. of electricity it is preferably formed of proper conducting material and grounded to the earth by means of the line C5. extended therefrom and this forms a shield determining the extent of the surface of the roller G to be eX'- posed to the charge,l while the grounded feed tray F also performs a similar function at the to of the roller. It has been found desirab e to heat the tray and for ythat purpose the electrical heater N, is shown in Fig. 2 which may be connected by' lines N and N2 with any source of power for that purpose. The

lheating of the materialcauses any residual charge thereon to be dissipated and' renders the material more susceptible to the new charge which is imparted thereto while heated from the charging electrode.

lIn order to define the circuit through the regulator and its relation in controlling the amount of current, it is assumed that the current flows frpm the positive pole of the static machine C3 to the pointed electrode H and across the intervening 'space to the sepa,- rating electrode G. This will cause an equal amount of negative electricity to flow out of the separating electrode across the gap by a series of disruptive discharges to the rod H2 L and thence through the line wire C4 and regulator O to the negative side of the static machine. unit of positive electricity delivered to the line C10 an exact equivalent amount of negative electricity is drawn up from the earth thfough the ground line C or straight across It therefore follows that for every the electrode G as this ground line vcan be l trodes and throu omitted withoutinaterially changing the results. As there cannot exist more of one polarity of electricity than another 1n a given .1 circuit, if a` resistance be interposed at the regulator O, it is substantiallv the same as if placed in line C10, and thereby regulates the amount -of current which may pass through the circuit. The ground line C is of service to the extent that it will ground out currents vthat occur from leakage or that may develop tor as it is not grounded, and the only current thatline C can carry would be that which leaks from line C* which in some cases is quite ap ireciable.

t is desirable in the successful working of the apparatus that the roller or other conducting' means for the material should be grounded to the earth so that zero potential ina be maintained to render the roller inactive electrically so that it is absolutely non-repulsive, The particles having been strongly polarized by the continuous convective charge remain clinging to the surface by virtue of their residual charges and retain such contact as long as these charges exist. As there is a-ditlerence in the period of time the particles maintain their polarity it is thus possible to make a large number of separations upon one roller for as the materials lose their polarity they can be dropped into dif- -ferent compartments during the rotation of the roller.

The construction of separating machine in connection with the interrupter for producing a varied charge or current has been speciically described and is claimed in our application Serial No. 225,852 so that furt-her description of the construction and operation thereof is not given herein, as the present divisional application presents a continuous or constant convective charge of one polarity but regulated through the return circuit to the generator taken from the discharging rod disposed immediately adjacent to the roller electrode.

(hie means for producing dielectric hysteretic impedance or lag of charge in the material to. be treated has been shown herein, but the invention contemplates the use of any means` for this purpose. and is not confined to 3 that herein shown nor to any particular forni of feeding and collecting elements for that VllI'PUS.

llaving'described otir invention and set forth its merits. what we claim and desire to lsecure b v Letters Patent is2- 1. The combination with the electrodes of an electro static separator, of means for producing a continuons convective current from one electrode to the other, means for feeding comminuted material between said elech said current, and means for separately collecting the separated particles.

2. The combination with the electrodes of an electro static separator, of means for producing a continuous convective current from one electrode to the other, means for feeding comminuted material to said latterelectrode, a regulator in circuit with one of the electrodes and having a member adapted to deliver a continuous convective charge therethrough, and means for separately collecting the se arated material."

3. he combination with al separating electrode and a pointed electrode, of a source of energy, means for supplying the pointed electrode with a continuous current of one polarity, means for feeding comminuted material between said electrodes, means incircuit with the source and one electrode for regulating the su ply of saidcurrent, and means for separate y collecting the separated particles.

4. The combination of a separating electrode and a charging electrode, of means for roducing a constant convective `current rom said charging electrode to the separating electrode, means for feeding comminuted material between the electrodes through the path ofsaid current, and means forseparately collecting the separated particles.

5. The combination with a separating electrode and a pointed charging electrode, of

a source of energ means for supplying the pointed electrode with a continuous current of one polarity, means for feeding comminuted material between said electrodes, and means for separately collecting the separated particles.

6. In an electro static separator, the combination with a se arating electrode and a pointed charging e ectrode, of a static machine having one pole connected directly to said pointed electrode, means for feeding comminuted material between said electrodes, means disposed at the discharging side` of the separating electrode connected to the opposite pole of the static machine, and means for separately collecting the separated particles.

7. In an electro static separator, the combination with a se arating electrode and a pointed charging e ectrode,4 of a static machine having one pole connected directly to said pointed electrode to supply a continuous current thereto, means for feeding comminuted material between said electrodes, a terminal disposed at the discharging side of the separating electrode and connected to the opposite pole of the static machine, means for separately collecting the separated particles, and a regulator disposed in the connection between the static machine \and the said terminal at the ilischarge side of separating electrode.

8. The combination with the electrodes of bination with a se arating electrode and a an electro static separator, of means for proi pointedcharging e ectrode, of a source of ducing acontinuous convective current from .I

one electrode to the other, means for feeding continuous supply in circuit with said charging electrode, a terminal disposed adjacent comminuted material between said electrodes l to the separating electrode and in circuit and through Asaid current, means for separately collecting the separated articles, and means for heating said materia and feeding it through said current while heated.

9. In an electro static separator, the colnbination with a separating electrode and a pointed char ing electrode, of a source of continuous supp y in circuit with said charging electrode, means disposed adjacent to the.

separating electrode and in circuit with the source of supply for regulating the supply of 'current thereto, means for feeding comminuted material between said electrodes, and means for separately collecting the separated particles.

l0. In an electro static separator, the coml i l l l l l l l i l l 1 with the source of sup ly, means for feeding comminuted materialp between said electrodes, means for separately collecting the separated articles, and a regulator disposed in circuit j etween the source of supply and one electrode andl comprising opposite terminals one being pointed and adjustable relative to the other.

In testimony whereofawe affix our signatures in presence of two witnesses. r

HENRY M. SUTTON. WALTER L. STEELE. EDWIN G. STEELE. /Vitnesses:

ERNEST L. LADD, EARL H. LILLY. 

